Tubal factor infertility (TFI) is caused by obstruction of the female genital tract and is responsible for 30% of the infertility found in women. Multiple infections with Chlamydia trachomatis leads to tubal pathologies including extensive tubal scarring, chronic salpingitis, distal tubal obstruction, pelvic inflammatory disease and ectopic pregnancy. Traditionally, the diagnosis of TFI is done through highly invasive methods such as hysterosalpingography and transvaginal salpingoscopy. In addition, there is no approved non-invasive clinical method for diagnosing the risk of developing TFI. Looking forward, there is a critical need for a noninvasive biomarker for TFI that could be used in therapy prediction and disease surveillance. The objective of this project is to identify novel and differentially expressd miRNA and genes regulated in CT pathogenesis that can predict the risk of developing TFI. miRNAs are fast emerging as diagnostic markers of other infectious diseases and cancer and they have been reported to regulate female reproductive tract development. We recently reported that miRNA was dysregulated in a murine model of Chlamydia-induced TFI. In this study we plan to identify novel and differentially expressed miRNA linked to the pathogenesis of Chlamydial infection leading to TFI. We also plan to identify genes whose expressions are strongly regulated by Chlamydia infection and are associated with TFI. The molecular signatures that will be acquired from this study are expected to provide a pathway to future design of a diagnostic marker for TFI. This study is expected to have a positive impact on the reproductive health of women and children by reducing the impact of TFI.